bfc - Brainf*ck compiler in C++ and assembly [WIP]

[Nineshadow]

https://github.com/Nineshadow/bfc

WHAT IS BFC?bfc is a brainfuck compiler which uses assembly and c++.________________________________________________________________________________________Version : 0.9________________________________________________________________________________________HOW TO USE :bfc.exe generates an assembly source file which can then be compiled into an executable.To generate this assembly soure file :(while in the same directory as bfc.exe)bfc.exe <input_file> <output_file>Then, you can transform the assembly source file(.s) into an executable using g++ :g++ -o <name_of_exec> <asm_source>You can also use help to get these instructions :bfc.exe helpOr, to skip these 2 steps, you can use compile.exe.The syntax is the same :compile.exe <input_file> <output_file>Still a little buggy._________________________________________________________________________________________PREREQ : g++ installed_________________________________________________________________________________________FEATURES :This compiler currently doesn't support all of the instructions that the brainfuck language has, as it's still very early in development.Lists of currently supported instructions:'>' - increment pointer'<' - decrement pointer'+' - increment value at pointer'-' - decrement value at pointer'.' - output value at pointer',' - input value at pointerAlso, the array in which you are free to move supports only integers for the moment. I realized that it should have been characters way too late, so I'm going to make a proper version later(that will hopefully also have instructions for the loops)__________________________________________________________________________________________WHAT IS BRAINFUCK :Brainfuck is an esoteric programming language, the ungodly creation of Urban Müller, whose goal was apparently to create a Turing-complete language for which he could write the smallest compiler ever, for the Amiga OS 2.0. His compiler was 240 bytes in size. (Though he improved upon this later -- he , at one point, said that he had managed to bring it under 200 bytes.) A Brainfuck program has an implicit byte pointer, called "the pointer", which is free to move around within an array of 30000 bytes, initially all set to zero. The pointer itself is initialized to point to the beginning of this array.The Brainfuck programming language consists of eight commands, each of which is represented as a single character.> 	Increment the pointer.< 	Decrement the pointer.+ 	Increment the byte at the pointer.- 	Decrement the byte at the pointer.. 	Output the byte at the pointer., 	Input a byte and store it in the byte at the pointer.[ 	Jump forward past the matching ] if the byte at the pointer is zero.] 	Jump backward to the matching [ unless the byte at the pointer is zero.The semantics of the Brainfuck commands can also be succinctly expressed in terms of C, as follows (assuming that p has been previously defined as a char*):> 	becomes 	++p;< 	becomes 	--p;+ 	becomes 	++*p;- 	becomes 	--*p;. 	becomes 	putchar(*p);, 	becomes 	*p = getchar();[ 	becomes 	while (*p) {] 	becomes 	}___________________________________________________________________________________________MISC :In ./asm_instructions you can find text files with the assembly instructions corresponding to some C/C++ statements/commands, both in AT&T(not yet finished) and Intel syntax../asm_test : used for finding out the corresponding assembly instructions.You can compile a .cpp/.c file dirrectly into assembly source code with gcc/g++ :g++ -S <input_file>In ./src you can find the source code for the compiler, for both a char(WIP) and int version.In ./tests you can find sample brainfuck sources you could compile. Not a whole lot of them so far.____________________________________________________________________________________________REASON OF PROJECT :For fun and to exercise with assembly.Also to test how github works  .____________________________________________________________________________________________UPDATES :0.9 - second release, added loops, still only using integers. Version 1.0 will use characters. Also, please don't critique the jump from 0.1 to 0.9 directly. I feel like it's has an almos full feature set, hence the 0.9. 0.1 - first release, didn't have support for loops and only worked with integers

It's 90% complete! If you find any issues, please report them. I'm also open to ideas

 

 

 

 

UPDATE 0.9 :

The long awaited moment ( by no person ever) has arrived! This brainfuck
compiler now has support for loops. You can now use any number of
brackets that you'd like.

[flibberdipper]

Also, do you guys have any suggestions on how to do the loops in assembly?

I know asm doesn't have any while loops, but it has jumps. How should I implement those? I summon you, @Ciccioo !

Sex with unicorns.

 

And then there's me, learning how to use PhotoShop and Premiere, and giving zero fucks that he can only make Visual Basic programs with tutorials.

[Stuff_]

To do loops, you compare and jump to the corresponding label (in IA32 at least) 

 

More specifically, compare 2 registers.

 

Make the jump, change the value, and do the comparison once again.

[Nineshadow]

To do loops, you compare and jump to the corresponding label (in IA32 at least) 

Yeah, just thinking about the implementation D: .

[Stuff_]

Yeah, just thinking about the implementation D: .

Consider this simple c program:

 

int simple_jump(int x, int y, int z) {

   if (x == 0)

      return y-z;

   return z-y;

}

 

IA32 might compile to:

 

simple_jump:

        pushl   %ebp

        movl    %esp, %ebp

 

        cmpl    $0, 8(%ebp)     // compare x to 0

        jne     .L2             // jump if x != 0

                                // get here if x == 0

        movl    12(%ebp), %eax  // y into %eax

        subl    16(%ebp), %eax  // y - z into %eax

        jmp     .L3             // done

.L2:                            // this is the case x != 0

        movl    16(%ebp), %eax  // z in %eax

        subl    12(%ebp), %eax  // z - y in %eax

 

.L3:                            // common return

        popl    %ebp

        ret

[Nineshadow]

Sex with unicorns.

 

And then there's me, learning how to use PhotoShop and Premiere, and giving zero fucks that he can only make Visual Basic programs with tutorials.

Ah, come on, it's not that hard. I gotta say this was pretty damn easy.

I did it just for fun and exercise(and to see how github works).

[flibberdipper]

Ah, come on, it's not that hard. I gotta say this was pretty damn easy.

I did it just for fun and exercise(and to see how github works).

It's nowhere near as easy as PhotoShop. And I get bored just typing and typing and typing... And typing... Video editing and photo edits are kinda my favorite thing to do, I guess.

[Ciccioo]

I summon you, @Ciccioo !

with that said, this should translate quite naturally to a conditional jump instruction (not that i would know how it works)

 

@Stuff_ 's example looks exaustive enough

[Nineshadow]

UPDATE 0.9 :

The long awaited moment ( by no person ever) has arrived! This brainfuck
compiler now has support for loops. You can now use any number of
brackets that you'd like.

 

@Ciccioo

 

I gotta say my work is 90% complete right now. Only need to change the array in which you can move the pointer to the type that brainfuck uses. Currently it's working with integers.

 

And the jumps weren't even all that hard. You just needed to have some knowledge of assembly, which I kinda lacked. After I had worked for like half an hour on the instructions for a jump, it just crashed.Then for the next 3 hours I kept debugging.Heck , I even made a version in C. Only to go back to the C++ vesion to discover that I had to change 1 letter and 1 instruction.I feel like an idiot.

This is what I'm talking about, from this :

cmp    %eax , 0je endLoop+countID 

to this:

testl   %eax , %eaxjz endLoop+countID